Wiring a pump

mrskittle

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This is brewing related but definitely a topic I haven't seen addressed.

I got this pump for my camper a couple of years ago but ended up using it for brewing instead. It's just for circulating ice water in my wort chiller. My issue is that it came ready to wire into a 12v system and I've been using a full-size battery to power it. Besides the inconvenience of lugging around a battery, I need to get rid of it to collect the core fee so I can buy new batteries for my camper. I feel like I should be able to find a 12v power adapter that I can wire up so I can just plug the pump into a regular outlet. The problem is that I don't know where to find one that fits the pump's specifications. I think I just need a plug that is rated around 3-3.5 amps. Any ideas?

20210125_102148.jpg
 
Yeah I agree with Voltage, that should work fine.
 

I just knew someone would have the answer. I think brewing attracts lots of folks with different technical backgrounds. I figured there'd be some electricians around. Maybe it is just a coincidence that the first response came from "High Voltage Man"!

This looks perfect! I imagined a wire with the cube that plugs into the wall but this is just a different configuration. Let me just clarify something first. The 5 amp rating on the plug is the max it can provide, and the 3.5 on the pump is the max it can draw. Right? The ac adapter can supply up to 5 amps but will only supply what the pump demands.

Donoroto, you must be more adept at DIY wiring than I am because the parts you linked to are over my head.
 
There are zillions of possible alternatives. As for a connector, most any connector can handle 4 Amps. Check at your local automotive store, look for something like this:
https://www.sciplus.com/2pin-connector-46518-p
This is would be a good connector to use. Red positive, black negative.
The 5 amp rating on the plug is the max it can provide, and the 3.5 on the pump is the max it can draw. Right? The ac adapter can supply up to 5 amps but will only supply what the pump demands.
The power supply I put a link to is a LED power supply and it will handle the pump just fine. I wouldn't put anything else on the power supply.
 
Donoroto, you must be more adept at DIY wiring than I am because the parts you linked to are over my head.
Yeah, sorry. That second power supply is like a laptop brick and only $10. Not just a DIYer but also a cheapskate.
 
Yeah, sorry. That second power supply is like a laptop brick and only $10. Not just a DIYer but also a cheapskate.

I'd be thrilled with a $10 fix but I'm not sure how to make the laptop brick work for my application. It doesn't come with a plug-in or separate pos/neg wires.

Now that i realize your 'Occupation' is a retired engineer, its makes sense that you see something workable where I don't.
 
doesn't come with a plug-in or separate pos/neg wires.
Sure it does. The electric cord is the exact same type as used for a computer (aka "IEC Cord") and the other end has some connector on it, cut it off (scissor) to reveal the two wires inside. Likely one red and one black, as normally expected.
 
Yeah you just cut the weird laptop plug off and there should be 2 wires in it for 12VDC.
 
PXL_20210125_230236346.jpg
I tossed out an old laptop power supply this morning. So I grabbed it and chopped the end off and you can see 3 wires. According to US standards black would be negative (aka hot) and white would be positive (aka neutral). Not sure about the blue wire. If it was a ground wire it would be green.
 
View attachment 13869 I tossed out an old laptop power supply this morning. So I grabbed it and chopped the end off and you can see 3 wires. According to US standards black would be negative (aka hot) and white would be positive (aka neutral). Not sure about the blue wire. If it was a ground wire it would be green.
Do you have your terms reversed there? Negative, would be ground, positive would be hot.
 
how to make the laptop brick work
The laptop brick would work if you found one with a 12 v rating (up to 13.5 v dc rating would be fine). The DC side cable could be cut and stripped to expose the wires. If it has 2 wires, red and black.. the red would be +.
If it has 3 wires, black blue and white... the white would be +, black -. the blue is a sensing circuit wire and would not be needed. Problem is the bricks typically provide a different voltage, not 12 v. (many times 19.5 v DC)
Your other concern is more or less correct... if you use a plug rated at 5 amps... that is indicating that the plug material can support or handle up to 5 amps of current flowing through it without being a hazard. The motor that you have is rated to pull 3.5 amps with source voltage of 12 v DC and the motor will draw/pull up to 3.5 amps when it is working at rated flow/pressure... it may draw a little less than that, depending on the setup you put it in.

Easier than worrying about a brick and trying to wire it up... would be to purchase a power supply with termination points available and marked. Here is one I found on a popular online store....
12vdc.JPG
 
Amen positive is always (Hot) usually the red wire. I'm no electrician but your multimeter will help.
 
Yeah, sorry. That second power supply is like a laptop brick and only $10. Not just a DIYer but also a cheapskate.

Cheap Bastards UNITE! And in that spirit, Wire Nuts make great connectors! Keep an eye on your wattage rating...if my math and recall of the Power Law (P/IxE) is right, there is not much overhead there.
 
With a device like a pump, you can connect it backwards with no lasting ille ffects, but of course the pump would run backwards. If that happens, swap the wires. 60 watts divided by 12 volts equals 5 Amps, plenty for a pump rated at 4 A maximum.

The second link I posted above is for a laptop-like power supply but with a 12 volt output at 5 A for $10.
 
Thank you all for the input. It's been extremely helpful. Now that I've got a good idea of what I need, there are a few local stores that I'll have to check out. There's a dive of a surplus store nearby that I think will have the laptop-like power supply.
 
Note that the pump can handle between 9 and 14.4 volts, so don't need to be too picky. Higher voltages make it run faster. It must be able to deliver 4 amps minimum. Just ask the folks at the surplus store, they probably have something that'll work.
 
I tossed out an old laptop power supply this morning. So I grabbed it and chopped the end off and you can see 3 wires.

If you look on the power brick it should have a diagram for the female plug that shows if center is (+) or (-). The ring will be the opposite. Since it's three wires there's probably two center conductors. The third wire is most likely to communicate with the charge controller in the laptop.
 
New Amen positive is always (Hot) usually the red wire. I'm no electrician but your multimeter will help.

There are positive ground DC systems. For instance older autos from the UK used 6volt Positive ground. Trust but verify. <g>
 

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